mills



(No Model.) 3 Sheets-Sheet 1'. J. MILLS. STEAM BOILER.

' Ne. 423,791. Patented Mar. 1 1890.

F101 F162. no.3, F104. no.5. FIGS.

N. PETERS. Pholmuum m h n Washington, D C.

(No Model.)

J. MILLS.

STEAM BOILER.

FIG. l2.

1 90000 000 o o o o 0 0000000.

WITNESSES Mv/ mM MQW/M 3 Sheets-Sheet 2.

Patented Mar. 18, 1890.

3 Sheets-Sheet a. J. MILLS. STEAM BOILER.

Patented Mar. 18, 1890.

(No Model.)

FIIG.

ooeooooooeeooogofl ll l l I I l l III N- PETERS. Phuln-Lithngnpllen Walhinflou D L UNITED STATES ATENT OFFICE.

JOHNSON MILLS, OF PRESTWIOH, COUNTY OF LANCASTER, ENGLAND.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 423,791, dated March 18, 1890. Application filed November 19, 1889. Serial No. 330,848- No model.) Patented in England June 17, 1889, No. 9,938.

To all whom it may concern.-

Be it known that I, JOHNSON MILLs, a subject of the Queen of Great Britain, and a resident of Prestwich, in the county of Lancaster, England, have invented certain new and useful Improvements in Steam-Boilers,(for which I have obtained a patent in Great Britain, No. 9,938, dated June 17, 1889,) of which the following is a full, clear, and exact specification thereof.

The improvements which are the subject of this invention relate to the form of headers which in water-tube steam-boilers are used as a means of supporting and connecting one of the vertical rows of the series of inclined tubes of which said steam-boilers are composed with the upper steam and water drum, and are in contradist-inction to water-slabs, which in like boilers are employed for connecting two'or more vertical rows of the series of inclined tubes with the upper steam and water drum.

The object of this invention is to promote free circulation of steam and water through the tubes and headers and their connections with the steam and water drum. This is obtained by the use of a form of header having a larger internal area at the upper end, as is hereinafter described, by which more than one nipple to each vertical row of inclined tubes may be fitted either one over the other or placed zigzag for the purpose of connecting each of said headers to the water box or pocket attached to steam and water drum, the number of nipples used being proportionate to the number of inclined tubes connected to each header in lieu of one nipple only being employed for a like purpose, as hitherto.

In this invention I construct a headereithcr of raw iron or mild steel or other suitable metal, and of an angular elliptical or circular steam and water drum two or a greater number of nipples, as may be required, placed in a vertical row in lieu of only one nipple, as hitherto. I place one side of the lower part of said header at right angles to one-vertical row of inclined tubes. I connect the ends of said tubes to aforesaid header either in one vertical row or in a zigzag form. The hereinabove described header may also in like manner be employed at rear end of the boiler.

In order more clearly to describe this my invention, I have annexed hereunto two sheets of drawings. In the several views therein illustrated similarletters refer to similar parts.

Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 are side and end views of various forms of taper header. Fig. 12 is a side view, and Figs. 13 and 14: end and side views, respectively, showing part of steam and water drums with the tapered headers in position.

In the views, a is the header; 1), vertical or zigzag row of a series of inclined tubes O, the nipples, which in Figs. 1 to 9 are represented as placed horizontally, and in Figs.10 and 11 the nipples are placed vertically. The side a of header A is represented placed at right angles to inclined tubes b. The side A may be either vertical or at an inclination, according to the capacity required in the upper part A of the header A. By these means a header is formed which has greater capacity at the upperend than at the bottom.

In Figs. 12, 13, and 14. I have shown part of steam and water drum with pockets and headers, as hereinabove described, placed in position so as to support and connect vertical rows of the series of inclined tubes with the upper steam and water drum f by means of two or more nipples, which are placed horizontally in a vertical row.

By the fOllllDfhGtClGl' as above described the steam is more freely separated from the water, and the circulation of steam and water through the inclined tubes is not impeded, inasmuch as the header is wider and of greater capacity at the part where the water from the upper tubes meets the upward flow of the water from the lower tubes, and free circulation is by these means obtained. I form caps or covers g in the hereinbefore-described headers, in order to allow the nipples andtubes to be more readily examined from the outside and at the end of the boiler.

Having now particularly described and ascertained the nature of my said invention and in what mannerthe same is to be formed, I declare that what I claim is- V In a Water-tube steam-boiler, a steam-drum provided With a depending pocket, in combination with independent headers having inclined sides, with which each row of vertical tubes connect, said headers also having a vertical side parallel with the pocket and being independently connected to said pocket by nipples, substantially as shown and described. In testimony that I claim the foregoing I have hereunto set my hand this 1st day of November, 1889.

JOHNSON MILLS. Witnesses:

JONATHAN GREsTY, THOMAS PRESCOTT. 

